Space and tech

How a satellite the size of a loaf of bread rides up in a pod, unfolds its solar wings, turns without rockets, takes pictures of Africa and sends them home in a ten-minute radio pass.

How a satellite the size of a cereal box keeps its camera pointed at a flooding river, thinks about the pictures, and beams a flood map down to the ground.

How a phone on a boda-boda's handlebar finds its place on the map, by timing radio signals from satellites 20,000 km up.

How a two-stage rocket carries a small satellite to orbit: fuel and oxygen tanks, turbopumps, a roaring nozzle, and empty stages dropped along the way.

How a space station keeps people alive 400 km up: pressurised modules, solar arrays, radiators, oxygen made from water, and Africa passing below every 90 minutes.

How a six-wheeled robot geologist climbs rocks, drills cores, powers itself and talks to Earth from 225 million kilometres away.

How a gold mirror behind a five-layer sunshield, 1.5 million km from Earth, sees the infrared glow of the first galaxies, and how Africa's radio dishes listen from the ground.

How a curved wing full of fuel lifts a 230-tonne airliner, and how its slats, flaps, ailerons and spoilers change its shape for every part of a flight.

How four spinning rotors, a tiny computer full of motion sensors and a battery keep a drone steady in the air, and how changing just the rotor speeds steers it.

How a bag of hot air lifts a basket of people at dawn: the envelope, the propane burner, buoyancy, the parachute vent, and steering with the wind.

How a lithium-ion battery stores sunshine for the night: lithium ions shuttle between graphite and metal oxide inside, while electrons do the work in the wire outside.

How a six-jointed robot arm in a car plant knows where its hand is, works out how to reach a point, and picks parts off a moving line all day without tiring.

How a spinning laser times its own echoes to measure the world in millions of dots, steering self-driving cars and finding lost cities under the bush.

How a battery, an inverter and one spinning motor move a car with no engine, no exhaust and no gears to change, and how it gets its energy back when it slows down.

How a cable no thicker than a garden hose, lying on the bottom of the Atlantic, carries Africa's messages, videos and calls to Europe as flashes of light.

How a speck of silicon becomes a switch with no moving parts, and how billions of them let a phone think.

What happens in the fifth of a second between a caller speaking in Kano and their family hearing them in Nairobi, about 3,500 kilometres away.

How a printer melts a thread of plastic and lays it down in hundreds of thin layers, building a real, useful part from nothing but a computer file.

How a giant magnet, a tank of liquid helium and pulses of radio make the hydrogen in your body sing, and turn its faint echo into a picture of the inside of your head.

How pulses of laser light, trapped in a strand of glass as thin as a hair, carry the internet under the road to your home.